Thoreau writes in his journal:
Am surprised to find the Polygonum Pennsylvanicum abundant, by the roadside near the bank. First saw it the other day at Brattleboro. This makes, as I reckon, twenty polygonums that I know, all but cilinode and Virginianum in Concord. Is not this a late kind? It grows larger than the Persicaria. Observed an Aster undulatus behind oak at foot of hill on Assabet, with lower leaves not heart-shaped . . .
